Slander is communication of false statements injurious to a person's reputation. You can sue if you have been defamed.

You might find my Legal Guide helpful " What Do I Tell My Lawyer?"

http://www.avvo.com/legal-guides/ugc/what-do-i-tell-my-lawyer

Online we cannot know what the other details are going on in your case because online we cannot find out those details. You need a lawyer. Check with a lawyer in your locale to discuss more of the details.

Good luck to you.

God bless.

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While it is true that defamation can be grounds for suit, you should be aware of the practical challenges. First, if she is slandering you (in other words making false statements orally), you will need to have a clear set of witnesses in mind that can/will testify accordingly. It would be far easier to prove if she was libellig you (in other words, making false comments about you in wiriting to third parties). Also, you should understand that truth is a defense, so the exact nature of her comments in context of your actions would need to be reviewed. In any event, as a practical matter you should consult with an attorney as to the possibility of sending a demand letter requesting cessation of the statements and a correction to the parties to whom she made such comments. However, given your statement that she is a drug user, that letter may have limited effect.

I hope this helps.

Disclaimer: This answer is for informational purposes only and does not constitute general or specific legal advice, nor create an attorney client relationship.